|
| DENON PMA-451 |
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| 49,800yen(around the 1977 time) |
PMA-701, the PCC loading Integrated Amplifier which inherited the technology of
PMA-501.
PCC is equipment which adds and negates a reverse cross talk to the cross talk of a phone pickup system.
In PMA-451, the attached record for adjustment is used, and two knobs are operated and adjusted. Thereby, an improvement hears to abbreviation-40dB in the most sensitive frequency band.
The power amplifier part consists of differential amplification
whole page direct connection OCL circuits, it is low impedance power supply
circuit composition, and a new style power transistor, such as double epitaxial
structure and the Mie diffusion structure, is adopted as an output final stage,
respectively.
In order to protect a speaker from an operation mistake or
an accident, speed of response builds in the very quick reliable protection
circuit.
Moreover, in consideration of the influence on sound quality, the
relay of special structure is adopted also about a relay.
In order to
improve the cross talk by interference between channels, the mutual intervention
is reduced by separating the power source of the circuit composition which made
the way become independent 2 system, and a power circuit with much current, and
the power source of a preamplifier circuit with little current.
In order
for the small signal sent from a record player to prevent deteriorating by
leading about and the change-over switch of wiring, a phone input circuit is
made into one line, and the input terminal is made to link with equalizer
amplifier directly.
A shield line and stray capacitance could be made small
by this, and input impedance is improved.
In order to improve a dynamic
cross talk, the power-source part has Puri Maine another winding wire power
transformer structure.
|
| Form |
Integrated Amplifier |
| <Power amplifier part>
|
| Circuit system |
Differential amplification whole page direct
connection pure complimentary OCL circuit |
| Dynamic output (IHF) |
140W (70W+70W, 8ohms) |
Output power
(both channel drive, a sine wave continuation output) |
45W+45W (8 ohms, 20Hz - 20kHz)
55W+55W
(4 ohms, 1kHz) |
| THD (Aux in->SP out) |
0.08% or less (at the time of an Output
power) |
| Cross modulation distortion (60Hz:7kHz=4:1)
|
0.1% or less (at the time of an Output power
Aux in->SP out) |
| Output bandwidth (IHF, both ch(es) drive)
|
5Hz - 50kHz |
| Output load impedance |
0.16ohm or less |
| Output terminal |
Speaker AorB: 4ohms - 16ohms
Speaker
A+B: 8ohm-16ohm
Headphone jack |
| <Preamplifier part>
|
| Input sensitivity/impedance |
Phono: 2.5Vrms/50kohm
Tuner, Aux,
Tape1, 2:150mVrms/85kohm |
| Phono maximum permissible input
(Phono->Rec out) |
150 or more (1kHz) mVrms |
| THD (1kHz) |
Phono->Rec out: Less than 0.008% (at the
time of 3Vrms output)
0.1% or less (at the time of the maximum except
take-off) |
| RIAA deflection |
20Hz-20kHz±0.3dB |
| An Output voltage/impedance |
Rec out: More than 150mVrms/50kohm
|
| Tone control |
Bass: 50Hz±10dB
Treble: 20kHz±10dB
|
| <PCC section> |
| Maximum permissible input |
9Vrms |
| After-cancellation phone cross talk |
Abbreviation-40dB |
| Transmission frequency response |
10Hz-50kHz+0 -1 dB |
| <Synthesis> |
| At the time of a transmission frequency
response |
20Hz-20kHz±0.75dB |
| Signal to noise ratio (IHF, A network, an
input short circuit) |
Phono: 75dB or more
Tuner, Aux, Tape1,
2:95dB or more |
| Cross talk (Phono->SP out) |
- 75dB or less (20Hz - 1kHz)
- 56dB or
less (20kHz) |
| Power receptacle |
switched: Two lines, a total of 150W
unswitched: One line, 100W |
| Power source |
AC100V, 50Hz/60Hz |
Power consumption
(Electrical Appliance and Material Control Law) |
125W |
| Dimensions |
Width 430x height 142.5x depth of 310mm
|
| Weight |
About 10.5kg |
| Attachment |
The record for adjustment |
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